(HealthDay News) -- Seasonal affective disorder (SAD) is a form of depression that is linked to the changing seasons. The most common form is winter depression, although a less common type is called summer SAD, the American Academy of Family Physicians says.

SAD may be related to the changes in the amount of daylight that fluctuates with the seasons, the academy says.

The most common symptoms of SAD include feelings of depression, fatigue, craving for starchy foods and weight gain as the specific season approaches.

In people with SAD, the same symptoms tend to return and ease every year at about the same times.